Sample workflow for LP digitization

This tutorial outlines a set of steps that can be used to digitize LPs with Audacity, ready for CD creation or loading into a digital jukebox or portable music player.

It is not the only way of working, there are many alternatives. Like any recipe it can be adapted to suit your personal needs.

UNDER CONSTRUCTION

Please note that this page is currently under construction - please bear with me for a few days while I work on it.

Overview

Most of the processing is carried out with Audacity, however I prefer to use Brain Davies’ ClickRepair software for the removal of clicks and pops as I believe that it does a better job of this than Audacity at present and is easier to use.

I work with Audacity set with Project Rate = 44.1kHz sample format 32-bit floating (the Audacity default. You can use 16-bit if you prefer. I export WAV files at 44.1kHz 16-bit PCM stereo as that is the standard required for making CDs and produces WAVs that are accepted for import by iTunes (and other music player software).

I prefer to work with one side of an LP at a time as this gives a smaller working set – you may prefer to record the whole LP and then do the processing

Workflow

1. Clean the LP
2. Check the recording levels
3. Capture one side of the LP in Audacity
4. Mark the approximate label points while recording - place cursor at point required and click [b]CTRL+B[/b]
5. Change the zoom level to “Fit Project” in window (makes future processing easier)
6. Export a single WAV for this side of the LP at 32-bit float
7. Leave the Audacity project open
8. Remove clicks and pops. Process this file through the ClickRepair software.
9. Return to the Audacity project and then Import the click-repaired WAV file back into the open project.
10. Delete the originally recorded track.
11. Move the label track to under the music track.
12. Carry on with remaining editing in Audacity:
    1. Clean the inter-track gaps,
    2. Adjust label positions,
    3. Possible fade-ins/outs etc.
13. Edit the labels with the song-names.
14. Adjust the amplitude of the recording.
15. Export Multiple to produce a set of WAVs at 44.1kHz 16-bit PCM stereo files
16. Repeat for next side of LP
17. Backup your WAV files.

Detailed steps

1. Clean the LP: cleaning the LP carefully and thoroughly before recording it will reduce the number of clicks and pops that you get and will improve the quality of your recording
2. Check the levels: play portions of the LP, or even the whole side of the LP, to check the recording levels that you set so that you avoid any clipping during the recording. Try to aim for a maximum peak of around –6dB (0r 0.5 if you have your meters et to linear rather than dB. Tip: enlarging the meter toolbars by clicking and dragging on the toolbar helps with this task.
3. Capture one side: I prefer to work with single sides of an LP as it gives a smaller working set. You can if you wish record both sides into the project prior to doing the processing. I tend to work at a zoom level which will show the whole side of the LP in the Audacity window.
4. Mark the approximate label points while recording: place your cursor at the approximate point required and click CTRL+B – alternatively you can mark the current recording point, while between tracks by using CTRL+M.
5. Change the zoom level to “Fit Project” in window – this will enable you to see the entire project, useful when the click-repaired file is reloaded later
6. Export a single WAV for this side of the LP at 32-bit float: ClickRepair will accept the file in this format and will return a processed file in the same format. You should keep this WAV file as a raw-capture file that you can return to later for any future re-editing.
7. Leave the Audacity project open: you are going to re-use shortly to work on the audio file that has been click-repaired
8. Remove clicks and pops. Process this file through the ClickRepair software: I change the ClickRepair defaults to: De-click 30, Crackle off ,Pitch Protection on, Method wavelet - select Reverse for particularly precussive recordings. ClickRepair will returns a 32-bit float WAV file with “-cr” appended to its file name for example: side<n> -cr.WAV
9. Return to the Audacity project and then Import the click-repaired WAV file back into the open project: use Audacity’s File>Import>Audio command to load in the repaired file. Note that it will load below the label track
10. Delete the originally recorded track:
11. Move the label track to under the music track: This step is not strictly necessary, I just prefer to work with the label track in its “normal” position below the music track. You can either do this by clicking and dragging the label track to below the click-repaired track – or you can use the “Move Track Down” command from the label track’s track menu.
12. Carry on with remaining editing in Audacity:
    1. Clean the inter-track gaps. These are rarely truly silent so I replace them with silence by selecting the gap and using CTRL+L: I also tend to shorten the inter track gap to around a maximum of 2 seconds.
    2. Adjust label positions: I normally leave a tail of 1.5 seconds and a run-in of 0.5 seconds.
    3. Possible fade-ins/outs: You may wish to more cleanly fade out the track ends and fade in the track beginnings (normally fadeouts should be longer and fade-ins, if required, quite short.
    4. You may find it easier to do: fade-out, silence gap, fade-in, shorten gap, adjust label position – in that order, one track at a time.
13. Edit the labels for song-names: I use 01 <song-name_1>, 02 <song-name_2>, etc. as this helps keep them in the right order for CD production or loading into iTunes etc. You may find that changing the zoom level will help you with this task - or you can tab to the next label by ensuring that the focus is on the current lable and then clicking the Tab key
14. Adjust the amplitude of the recording. I normally Use Effect > Amplify as my last editing step to bring the amplitude up to -1dB. I use Amplify rather than Normalize as Audacity’s Normalize effect operates on each stereo channel independently and can thus affect/damage the stereo balance. If your equipment is not balance you may prefer to use Normalize.
15. Export Multiple to produce a set of WAVs at 44.1kHz 16-bit PCM stereo files (this the Red Book standard for CDs). Audacity will down-sample on export from 32-bit to 16-bit and you may wish to ensure that dithering is applied. I use triangular dithering – you set the dithering in Preferences . See this article in the Audacity Wiki for an explanation of dithering.
16. Repeat for next side of LP
17. Backup your WAV files: you don't want to lose all that valuable work and do it all over again, do you? I use two separate external 1TB USB disks to hold my WAVs - each LP is stored in its own named folder by artist (or composer for classical) to make retrieval easier.

Options

1. You can use 16-bit throughout if required – it will reduce the space needed.
2. Some users may wish to remove subsonic rumble and low frequency noise. If so, this should be done in the workflow prior to the click removal steps. Whether you need to or not will depend on the quality of your turntable/arm/cartridge and its placement.
3. Some users may wish to remove any continuous noise such as hiss. If so, this should be done in the workflow after the click removal steps. Once the click repaired file has been loaded back into Audacity then Audacity’s Noise Removal too can be used to effect this. Whether you need to or not will depend on the quality of your LPs and your stylus/cartridge.
4. Some users may wish to apply compression as a final processing step, Chris's Compressor is often recommended for this.
5. You can work in AIFF rather than WAV with the ClickRepair software if required.

Links

|< Tutorial - Copying tapes, LPs or minidiscs to CD

Brian Davies's ClickRepair software can be accessed from here: http://www.clickrepair.net/

Link to: Chris's Dynamic Compressor